1.1 Analyzing Motion by Using Diagrams1.3 Predicting Motion from Graphs 1.4 Predicting Motion from Equations 1.5 Problem-Solving Strategies for Kinematics 1.6 Skier Races Downhill 1.8 Se
Trang 4Physics
Trang 6For users of the two-volume
edition, Volume 1 includes
Chapters 1–16 and Volume 2
17.7 Charges and Fields,
Electric Field Hockey,
Electric Field of
Dreams 563
*18.2 Charges and Fields 587
18.9 Molecular Motors, Optical Tweezers andApplications, StretchingDNA 607
19.2 Conductivity, Ohm‘s Law,Resistance in a Wire 620
19.3 Battery Voltage 624
19.4 Battery-Resistor Circuit,Signal Circuit 630
19.5 Circuit Constructions Kit(DC Only) 633
20.2 Magnets and Compass,Magnets and
Electromagnets 660
20.9 Faraday‘s ElectromagneticLab 681
21.3 Faraday‘s ElectromagneticLab, Faraday‘s Law, Generator 702
*22.3 Circuit Constructions Kit(AC+DC) 744
23.4 Radio Waves &
ElectromagneticFields 766
29.5 Band Structure, Conductivity 989
29.6 Semiconductors,Conductivity 991
Trang 81.1 Analyzing Motion by Using Diagrams
1.3 Predicting Motion from Graphs
1.4 Predicting Motion from Equations
1.5 Problem-Solving Strategies for
Kinematics
1.6 Skier Races Downhill
1.8 Seat Belts Save Lives
1.9 Screeching to a Halt
1.11 Car Starts, then Stops
1.12 Solving Two-Vehicle Problems
1.13 Car Catches Truck
1.14 Avoiding a Rear-End Collision
2.4 Rocket Blasts Off
2.5 Truck Pulls Crate
2.6 Pushing a Crate up a Wall
2.7 Skier Goes down a Slope
2.8 Skier and Rope Tow
2.9 Pole-Vaulter Vaults
2.10 Truck Pulls Two Crates
2.11 Modified Atwood Machine
3.1 Solving Projectile Motion Problems
3.2 Two Balls Falling
3.3 Changing the x-Velocity
3.4 Projectile x- and y-Accelerations
3.5 Initial Velocity Components
3.6 Target Practice I
3.7 Target Practice II
4.1 Magnitude of Centripetal Acceleration
4.2 Circular Motion Problem Solving
4.3 Cart Goes over Circular Path
4.4 Ball Swings on a String
4.5 Car Circles a Track
4.6 Satellites Orbit
5.1 Work Calculations
5.2 Upward-Moving Elevator Stops
5.3 Stopping a Downward-Moving Elevator
5.4 Inverse Bungee Jumper
5.5 Spring-Launched Bowler
5.6 Skier Speed
5.7 Modified Atwood Machine
6.1 Momentum and Energy Change
6.2 Collisions and Elasticity
6.3 Momentum Conservation and
6.8 Skier and Cart
6.9 Pendulum Bashes Box
6.10 Pendulum Person–Projectile Bowling
7.11 Race between a Block and a Disk
7.12 Woman and Flywheel Elevator: Energy Approach
7.13 Rotoride: Energy Approach
7.14 Ball Hits Bat
8.4 State Variables and Ideal Gas Law
8.5 Work Done by a Gas
8.6 Heat, Internal Energy, and First Law of Thermodynamics
8.12 Cyclic Process: Strategies
8.13 Cyclic Process: Problems
8.14 Carnot Cycle
9.3 Vibrational Energy
9.4 Two Ways to Weigh Young Tarzan
9.5 Ape Drops Tarzan
9.6 Releasing a Vibrating Skier I
9.7 Releasing a Vibrating Skier II
9.8 One- and Two-Spring Vibrating Systems
9.9 Vibro-Ride
9.10 Pendulum Frequency
9.11 Risky Pendulum Walk
10.1 Properties of Mechanical Waves
10.2 Speed of Waves on a String
10.4 Standing Waves on Strings
10.5 Tuning a Stringed Instrument: Standing Waves
10.6 String Mass and Standing Waves
10.7 Beats and Beat Frequency
10.8 Doppler Effect: Conceptual Introduction
10.9 Doppler Effect: Problems
11.1 Electric Force: Coulomb’s Law
11.2 Electric Force: Superposition Principle
11.3 Electric Force: Superposition Principle (Quantitative)
11.4 Electric Field: Point Charge
11.5 Electric Field Due to a Dipole
11.6 Electric Field: Problems
11.9 Motion of a Charge in an Electric Field:
Introduction
11.10 Motion in an Electric Field: Problems
11.11 Electric Potential: Qualitative Introduction
12.1 DC Series Circuits (Qualitative)
12.2 DC Parallel Circuits
12.3 DC Circuit Puzzles
12.4 Using Ammeters and Voltmeters
12.5 Using Kirchhoff’s Laws
12.6 Capacitance
12.7 Series and Parallel Capacitors
12.8 R–CCircuit Time Constants
13.1 Magnetic Field of a Wire
13.2 Magnetic Field of a Loop
13.3 Magnetic Field of a Solenoid
13.4 Magnetic Force on a Particle
13.5 Magnetic Force on a Wire
13.6 Magnetic Torque on a Loop
14.3 The Driven Oscillator
15.1 Reflection and Refraction
15.2 Total Internal Reflection
15.3 Refraction Applications
15.4 Plane Mirrors
15.5 Spherical Mirrors: Ray Diagrams
15.6 Spherical Mirror: The Mirror Equation
15.7 Spherical Mirror: Linear Magnification
15.8 Spherical Mirror: Problems
15.9 Thin-Lens Ray Diagrams
15.10 Converging Lens Problems
15.11 Diverging Lens Problems
15.12 Two-Lens Optical Systems
16.1 Two-Source Interference: Introduction
16.2 Two-Source Interference: Qualitative Questions
16.3 Two-Source Interference: Problems
16.4 The Grating: Introduction and Qualitative Questions
16.5 The Grating: Problems
Trang 9Hugh D Young is Emeritus Professor of Physics at Carnegie
Mellon University He earned both his undergraduate and
gradu-ate degrees from that university He earned his Ph.D in
funda-mental particle theory under the direction of the late Richard
Cutkosky He joined the faculty of Carnegie Mellon in 1956 and
retired in 2004 He also had two visiting professorships at the
University of California, Berkeley
Dr Young’s career has centered entirely on undergraduate
education He has written several undergraduate-level textbooks,
and in 1973 he became a coauthor with Francis Sears and Mark
Zemansky for their well-known introductory texts In addition to
his authorship of Sears & Zemansky’s College Physics, he is also
coauthor, with Roger Freedman, of Sears & Zemansky’s University
Physics
Dr Young earned a bachelor’s degree in organ performance
from Carnegie Mellon in 1972 and spent several years as
Associ-ate Organist at St Paul’s Cathedral in Pittsburgh He has played
numerous organ recitals in the Pittsburgh area Dr Young and his
wife, Alice, usually travel extensively in the summer, especially
overseas and in the desert canyon country of southern Utah
Trang 10College Physics
Hugh D Young
Carnegie Mellon University
9th Edition
Trang 11Director of Development: Michael Gillespie
Senior Development Editor: Margot Otway
Editorial Assistant: Steven Le
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Managing Editor: Corinne Benson
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Production Management and
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Cover Photo Credit: Mike Kemp/Rubberball/Corbis
Credits and acknowledgments borrowed from other sources and reproduced, with
permission, in this textbook appear on the appropriate page within the text or on p C-1
Copyright © 2012, 2007, 1991, Pearson Education, Inc., publishing as
Addison-Wesley, 1301 Sansome Street, San Francisco, CA, 94111 All rights reserved
Manufactured in the United States of America This publication is protected by
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Many of the designations used by manufacturers and sellers to distinguish their
products are claimed as trademarks Where those designations appear in this book,
and the publisher was aware of a trademark claim, the designations have been printed
in initial caps or all caps
Mastering Physics®is a registered trademark, in the U.S and/or other countries, of
Pearson Education, Inc or its affiliates
Library of Congress Cataloging-in-Publication Data
Young, Hugh D
Sears & Zemansky’s college physics.—9th ed / Hugh D Young
p cm
Includes bibliographical references and index
ISBN-13: 978-0-321-73317-7 (alk paper)
ISBN-10: 0-321-73317-7 (alk paper)
1 Physics—Textbooks I Sears, Francis Weston, 1898–1975 College physics
II Title III Title: College physics IV Title: Sears and Zemansky’s college physics
QC23.2.Y68 2012
530—dc22
2010046658College Physics—Complete Edition
ISBN 10: 0-321-73317-7; ISBN 13: 978-0-321-73317-7 (Student edition)
ISBN 10: 0-321-73315-0; ISBN 13: 978-0-321-73315-3 (Exam copy)
1 2 3 4 5 6 7 8 9 10—WBC—14 13 12 11 10
Trang 12Chapter 0 Mathematics Review 0-1
Mechanics
Chapter 1 Models, Measurements, and Vectors 1
Chapter 2 Motion along a Straight Line 29
Chapter 3 Motion in a Plane 68
Chapter 4 Newton’s Laws of Motion 99
Chapter 5 Applications of Newton’s Laws 128
Chapter 6 Circular Motion and Gravitation 161
Chapter 7 Work and Energy 188
Chapter 9 Rotational Motion 267
Chapter 10 Dynamics of Rotational Motion 294
Periodic Motion, Waves, and Fluids
Chapter 11 Elasticity and Periodic Motion 333
Chapter 12 Mechanical Waves and Sound 365
Chapter 13 Fluid Mechanics 407
Thermodynamics
Chapter 14 Temperature and Heat 441
Chapter 15 Thermal Properties of Matter 477
Chapter 16 The Second Law of
Thermodynamics 516
Electricity and Magnetism
Chapter 17 Electric Charge and Electric Field 545
Chapter 18 Electric Potential and Capacitance 582
Chapter 19 Current, Resistance, and
Direct-Current Circuits 618
Chapter 20 Magnetic Field and
Magnetic Forces 658
Chapter 21 Electromagnetic Induction 698
Chapter 22 Alternating Current 735
Chapter 23 Electromagnetic Waves and Propagation
of Light 761
Light and OpticsChapter 24 Geometric Optics 803
Chapter 25 Optical Instruments 837
Chapter 26 Interference and Diffraction 862
Modern PhysicsChapter 27 Relativity 899
Chapter 28 Photons, Electrons, and Atoms 932
Chapter 29 Atoms, Molecules, and Solids 971
Chapter 30 Nuclear and High-Energy Physics 1003
Appendix A The International System of Units A-1
Appendix B The Greek Alphabet A-3
Appendix C Periodic Table of the Elements A-4
Appendix D Unit Coversion Factors A-5
Appendix E Numerical Constants and Astronomical
Data A-6Answers to Odd-Numbered Problems A-8
Trang 13Problem-Solving Strategies coach students in how to approach specific types of problems.
This text’s uniquely extensive set
of Examples enables students to
explore problem-solving challenges
in exceptional detail
Consistent The Set Up / Solve / Reflect format,
used in all Examples, encourages
students to tackle problems thoughtfully
rather than skipping to the math.
Visual Most Examples employ a diagram—
often a pencil sketch that shows
what a student should draw.
NEW! Video Tutor Solution for Every Example
Each Example is explained and solved by an instructor
in a Video Tutor solution provided in the Study Area
of MasteringPhysics®and in the Pearson eText.
NEW! Mathematics Review Tutorials
MasteringPhysics offers an extensive set of assignable mathematics review tutorials, covering all the areas in which students typically have trouble.
䊳
䊳
L earn basic and advanced skills that help
solve a broad range of physics problems
Trang 14NEW! Passage Problems, which use the same reading-passage format as most MCAT questions, develop students’ ability
to apply physics to a real-world situation (often biological or biomedical in nature)
Problems in MasteringPhysics
Select end-of-chapter problems will now offer
additional support such as problem-solving
strategy hints, relevant math review and practice,
and links to the eText These new enhanced
problems bridge the gap between guided tutorials and traditional homework problems.
䊳
䊳
D evelop problem-solving confidence through a range
of practice options—from guided to unguided
About 20% of the End-of-Chapter Problems
are new or revised These revisions are driven
by detailed student-performance data gathered
nationally through MasteringPhysics.®
Problem difficulty is indicated by a three-dot ranking
system based on data from MasteringPhysics.
Trang 15D eepen knowledge of physics by building
connections to the real world.
NEW! PhET Simulations and Tutorials
76 PhET simulations are provided in the Study Area of the MasteringPhysics®website and in the Pearson eText In addition, MasteringPhysics contains 16 new, assignable PhET-based tutorials
NEW! Video Tutor Demonstrations and Tutorials
“Pause and predict” demonstration videos of key physics concepts
engage students by asking them to submit a prediction before seeing
the outcome These videos are available through the Study Area
of MasteringPhysics and in the Pearson eText A set of assignable
tutorials based on these videos challenge students to transfer their
understanding of the demonstration to a related problem situation.
Biomedically Based End-of-Chapter Problems
To serve biosciences students, the text offers
a substantial number of problems based on biological and biomedical situations.
Throughout the text, captioned photos apply physics to real situations, with particular emphasis
on applications of biomedical and general interest
䊳
䊳
䊳
Trang 16NEW! Pre-Built Assignments
For every chapter in the book, MasteringPhysics
now provides pre-built assignments that cover
the material with a tested mix of tutorials and end-of-chapter problems of graded difficulty
Professors may use these assignments as-is or
take them as a starting point for modification
Gradebook
• Every assignment is graded automatically.
• Shades of red highlight vulnerable students and challenging assignments
Gradebook Diagnostics
This screen provides your favorite weekly diagnostics
With a single click, charts summarize the most difficult problems, vulnerable students, grade distribution, and even improvement in scores over the course
Class Performance on Assignment
Click on a problem to see which step your students struggled with most, and even their most common wrong answers Compare results at every stage with the national average or with your previous class
M asteringPhysics is the most effective and widely used online science tutorial, homework, and assessment system available.
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Trang 17Echolocation in bats 3 BIO
Mars mission mistakes 7Train crash illustrates the importance
of precision in measurement 10Vectors in a caribou’s swim across
a river 14
the world” 32Average speed/average velocity
of a race car 37Negative acceleration of a drag racer 39Human centrifuge 42 BIO
Mechanisms in motor neurons 49 BIO
A car’s three accelerators 72Gravisensing in plant roots 73 BIO
Rate of change of velocity in juggling 77Ballistic spores 79 BIO
Human cannonball as projectile 82Uniform circular motion in global positioningsystems 87
first law 102Tablecloth trick: Inertia 103Bubble chamber image:
Studying particles 107Bacterial propulsion 111 BIO
Biathlete using Newton’s third law 113Rocket launch 115
Tug-of-war 116
Telescope mirror 129Liquid-filled accelerometer 134Rock climber using frictional forces 138Wet saw cutting stone 139
Molecular motors 140 BIO
Centripetal force in bobsledding 163Runner using Newton’s third law 170 BIO
Gravity map of the earth 173
Elasticity of tendons and ligaments 201 BIO
Carrying weight on the head 203 BIO
Energy expended in climbing
El Capitan 207 BIO
Cilia and fluid movement in the inner ear 207 BIO
Grasshopper’s catapult mechanism 208 BIO
Measuring a llama’s oxygen consumption 216 BIO
Work at the molecular scale 216 BIO
Conservation of momentum
in a bowling strike 235Momentum of sumo wrestlers 241Light sail 244
Frog’s legs demonstrating impulse 248 BIO
Center of mass in balancing acrobats 253Jet propulsion in jellyfish 255 BIO
angular velocity 269Velocipede direct-drive bicycle 274Storing energy in a flywheel 277Moon orbiting earth 282
Angular acceleration and the inner ear 303 BIO
Rotating DNA and torque 304 BIO
Oxen turning water-well lift 304Nanoengineered gears 306Andaman earthquake’s effects
on length of day 308Spinning dinner plates 313Rifling in a gun barrel 318
Weighing a fish 336Volume stress and strain shape the embryo 337 BIO
Buoyancy in deep-sea hatchetfish 337 BIO
Strength and elasticity
in a spider’s web 340 BIO
Nanobalance 348Foucault pendulum 353
Trang 18Wave generation in a surf pool 368
Superposition of mechanical waves
in water ripples 375
Bone flutes: Standing waves 384
Sound-wave vibrations
in the human ear 386 BIO
Prey location by barn owls 390 BIO
Use of sonar in search of shipwrecks 391
Doppler radar in meteorology 395
in a coffee drink 408
Measuring fluid pressure
in the human eyeball 412 BIO
Snowshoeing to reduce pressure 413
Floating in the Dead Sea 418 BIO
Water flow in plants 422 BIO
Turbulent flow in a meandering river 424
Roof blown off by hurricane 425
Bimaterial strips 447
Snowflakes 455
Heat stroke and hot tubs 457 BIO
Using a calorimeter to measure a cow’s heat
production 458 BIO
Heat conduction in predatory fishes 461 BIO
Hawaiian islands: Built by convective flow 465
Infared images 466 BIO
Solar car 467
of stars 478
Martian dust devil 480
Why aircraft cabins are pressurized 481 BIO
Scuba-diving hazards 483 BIO
High-temperature calibration of a platinum
resistance thermometer 485
Hydrogen affects planet size 489
Venus: An arid furnace 490
Nuclear submarines as steamships 495
Geothermal power in Iceland 518
”Bio-diesel” engines 522How a refrigerator works 523Photosynthesis 530 BIO
Energy cycles of the earth and its organisms 535
Zero-power homes 536
strike 546Salt water conducts electricity 549
”Static cling” in DNA 552 BIO
Atom-smashing with Van de Graaff generators553
Platypus sensing electric fields 558 BIO
Cells sensitive to electrical fields 560 BIO
Fish producing and using an electric field tosense its surroundings 565 BIO
Car acting as a Faraday cage in
an electrical storm 572
cell membrane 583 BIO
Patch clamp technique 586 BIO
Lightning bolt 587Bird perching on power line 589 BIO
Sandia Lab’s capacitor bank discharging 596Capacitors in cardiac defibrillators 604 BIO
Magnetic-levitation trains 622 Electric eels 625 BIO
Electrical signaling and tissue regeneration 629 BIO
Recharging ATP molecules 630 BIO
LED bicycle lights 631Wrist strap grounding electronics worker 643 BIO
magnetic field 661 BIO
Magnetic resonance imaging 664 BIO
Microwave ovens 667Direct-current motors 673Coaxial cable 677Magnetohydrodynamic pump 683
Trang 19Chapter 21 Induction cooktop 699
Portable energy pack 705Using an electromagnetic tether to deorbitsatellites 710
Recharging pad for electronic devices 712Using magnetic fields to catch red-light runners 716
Step-down transformers 717Detecting tiny magnetic fields in the brain 719 BIO
L –C circuits in tuning knobs 725
Electric pulse treatments for skin cancer 748 BIO
Power surge protection 749
Cerenkov radiation in a nuclear reactor pool 763
Galaxy in different spectral regions 765 BIO
Ultraviolet vision in animals 765Seedling cells guiding light 781 BIO
Physics of a double rainbow 783The human eye’s response to sunlight 784 BIO
Light polarization in cuttlefish 785 BIO
Photoelastic stress analysis 789
Side-view convex mirrors 811Seeing in focus 816 BIO
Green flash at sunset 817Diamond lenses used in optical data storage 821
Compound eyes 841 BIO
Animals’ focusing mechanisms 842 BIO
Eyeglass lenses 843X-ray telescope 850Telescope mirrors 852
Nonreflective coating on museum cases 872Structural color in butterflies 873 BIO
Phase-contrast microscopy 877 BIO
Using diffraction gratings to measure DNA 880 BIO
Reflection diffraction grating in CDs 880Modern telescopes using
interferometry 888
of reference 901Time at the finish line 906Time travel 909
Space and time 914Nuclear power: 920
Fireworks 941Ruby lasers 951Boron neutron capture therapy for brain cancer 956 BIO
Electron microscopy 961 BIO
DNA double helix: Bonding 984 BIO
Diamonds and graphite 990Electron vacancies
in semiconductors 993Transistor radio 996Using quantum physics to look at living tissues 997 BIO
Penetrating power of different types
of radiation 1012Radiocarbon dating 1017 BIO
Residence time of radionuclides
in the body 1019 BIO
Gamma-ray radiosurgery 1020 BIO
Nuclear medicine: Bone scans 1021 BIO
xvi
Trang 20“Is physics hard? Is it too hard for me?” Many students are apprehensive about
their physics course However, while the course can be challenging, almost
cer-tainly it is not too hard for you If you devote time to the course and use that time
wisely, you can succeed
Here’s how to succeed in physics.
1 Spend time studying The rule of thumb for college courses is that you
should expect to study about 2 to 3 hours per week for each unit of credit, in addition to the time you spend in class And budget your time: 3 hours every
other day is much more effective than 33 hours right before the exam The good news is that physics is consistent Once you’ve learned how to tackle one topic, you’ll use the same study techniques to tackle the rest of the course So if you find you need to give the course extra time at first, do so and don’t worry—it’ll pay dividends as the course progresses.
2 Don’t miss class Yes, you could borrow a friend’s notes, but listening and
participating in class are far more effective Of course, participating means
paying active attention, and interacting when you have the chance!
3 Make this book work for you This text is packed with decades of teaching
experience—but to make it work for you, you must read and use it actively Think about what the text is saying Use the illustrations Try to solve the
Examples and the Quantitative and Conceptual Analysis problems on your
own, before reading the solutions If you underline, do so thoughtfully and not
mechanically.
A good practice is to skim the chapter before going to class to get a sense for the topic, and then read it carefully and work the examples after class
4 Approach physics problems systematically While it’s important to attend
class and use the book, your real learning will happen mostly as you work problems—if you approach them correctly Physics problems aren’t math
problems You need to approach them in a different way (If you’re “not good
at math,” this may be good news for you!) What you do before and after ing an equation is more important than the math itself The worked examples
solv-in this book help you develop good habits by consistently followsolv-ing three
steps—Set Up, Solve, and Reflect (In fact, this global approach will help you
with problem solving in all disciplines—chemistry, medicine, business, etc.)
5 Use campus resources If you get stuck, get help Your professor probably
has office hours and email; use them Use your TA or campus tutoring center if you have one Partner with a friend to study together But also try to get
unstuck on your own before you go for help That way, you’ll benefit more
from the help you get.
So remember, you can succeed in physics Just devote time to the job,
work lots of problems, and get help when you need it Your book is here to help Have fun!
SET U P
Think about the physics involved in the
situation the problem describes What
information are you given and what do
you need to find out? Which physics
principles do you need to apply?
Almost always you should draw a
sketch and label it with the relevant
known and unknown information
(Many of the worked examples in this
book include hand-drawn sketches to
coach you on what to draw.)
SOLVE
Based on what you did in Set Up,
identify the physics and appropriate
equation or equations and do the
alge-bra Because you started by thinking
about the physics (and drawing a
dia-gram), you’ll know which physics
equations apply to the situation—
you’ll avoid the “plug and pray” trap
of picking any equation that seems to
have the right variables
R EF LECT
Once you have an answer, ask yourself
whether it is plausible If you
calcu-lated your weight on the Moon to be
10,423 kg—you must have made a
mis-take somewhere! Next, check that your
answer has the right units Finally,
think about what you learned from the
problem that will help you later
Trang 22and proven innovations in education research, we have revised and enhanced previous material and added new features focusing on more explicit problem- solving steps and techniques, conceptual understanding, and visualization and modeling skills Our main objectives are to teach a solid understanding of the fundamentals, help students develop critical thinking and quantitative reasoning, teach sound problem-solving skills, and spark the students’ interest in physics with interesting and relevant applications.
This text provides a comprehensive introduction to physics at the beginning college level It is intended for students whose mathematics preparation includes high-school algebra and trigonometry but no calculus The complete text may be taught in a two-semester or three-quarter course, and the book is also adaptable to
a wide variety of shorter courses.
New to This Edition
• New Chapter 0 (Mathematics Review) covers math concepts that students
will need to use throughout the course: Exponents; scientific notation and powers of 10; algebra; direct, inverse, and inverse-square relationships; log- arithmic and exponential functions; areas and volumes; and plane geometry and trigonometry This review chapter includes worked examples and end- of-chapter problems.
• New margin applications include over 40 new biosciences-related
applica-tions with photos added to the text, including those focused on cutting-edge technology BIO icons signify the bio-related applications.
• Changes to the end-of-chapter problems include the following:
• 15–20% of the problems are new.
• Many additional biosciences-related problems.
• One set of MCAT-style passage problems added at the end of most
chapters, many of them bio-related.
The addition of new biological and biomedical real-world applications and problems gives this edition more coverage in the biosciences than nearly every other book on the market.
• Over 70 PhET simulations are linked to the Pearson eText and are provided
in the study area of the MasteringPhysics website (with icons in the print text) These powerful simulations allow students to interact productively with the physics concepts they are learning PhET clicker questions are also included
on the Instructor Resource DVD.
• Video Tutors bring key content to life throughout the text:
• Dozens of Video Tutors feature “pause-and-predict” tions of key physics concepts and incorporate assessment as the student
demonstra-progresses, to actively engage the student in understanding the key ceptual ideas underlying the physics principles.
con-• Every Worked Example in the book is accompanied by a Video Tutor Solution that walks students through the problem-solving process, pro-
viding a virtual teaching assistant on a round-the-clock basis.
• All of these Video Tutors play directly through links within the son eText Many also appear in the Study area within MasteringPhysics.
Trang 23• Assignable MasteringPhysics tutorials are based on the Video Tutor Demonstrations and PhET simulations.
• Video Tutor Demonstrations will be expanded to tutorials in tering by requiring the student to transfer their understanding to a new
Mas-problem situation so that these will be gradable and distinct from the
“pause and predict” demonstrations alone.
• Sixteen new PhET tutorials enable students to not only explore the
PhET simulations but also answer questions, helping them make nections between real-life phenomena and the underlying physics that explain such phenomena.
con-Key Features of College Physics
• A systematic approach to problem solving To solve problems with
confi-dence, students must learn to approach problems effectively at a global level, must understand the physics in question, and must acquire the specific skills needed for particular types of problems The Ninth Edition provides research- proven tools for students to tackle each goal.
• The worked examples all follow a consistent and explicit global solving strategy drawn from educational research This three-step approach puts special emphasis on how to set-up the problem before trying to solve it, and the importance of how to reflect on whether the answer is sensible.
problem-• Worked example solutions emphasize the steps and decisions students often
skip In particular, many worked examples include pencil diagrams: drawn diagrams that show exactly what a student should draw in the set-up
hand-step of solving the problem.
• Conceptual Analysis and Quantitative Analysis problems help the students
practice their qualitative and quantitative understanding of the physics The Quantitative Analysis problems focus on skills of quantitative and propor- tional reasoning—skills that are key to success on the MCATs The CAs and QAs use a multiple-choice format to elicit specific common misconceptions.
• Problem-solving strategies teach the students tactics for particular types of
problems—such as problems requiring Newton’s second law, energy vation, etc.—and follow the same 3-step global approach (set-up, solve, and reflect).
conser-• Unique, highly effective figures incorporate the latest ideas from educational research Extraneous detail has been removed and color used only for strict peda- gogical purposes—for instance, in mechanics, color is used to identify the object
of interest, while all other objects are grayscale Illustrations include helpful blue annotated comments to guide students in ‘reading’ graphs and physics fig- ures Throughout, figures, models, and graphs are placed side by side to help students ‘translate’ between multiple representations Pencil sketches are used
consistently in worked examples to emphasize what students should draw.
• Visual chapter summaries show each concept in words, math, and figures to
reinforce how to ‘translate’ between different representations and address ferent student learning styles.
dif-• Rich and diverse end-of-chapter problem sets The renowned Sears &
Zemansky problems, refined over five decades of use, have been revised, expanded and enhanced for today’s courses, based on data from Mastering- Physics.
• Each chapter includes a set of multiple-choice problems that test the skills
developed by the Qualitative Analysis and Quantitative Analysis problems in the chapter text The multiple-choice format elicits specific common miscon- ceptions, enabling students to pinpoint their misunderstandings.
Trang 24• The General Problems contain many context-rich problems (also known as
real-world problems), which require students to simplify and model more
complex real-world situations Many problems relate to the field of biology
and medicine; these are all labeled BIO.
• Connections of physics to the student’s world In-margin photos with
explanatory captions provide diverse, interesting, and self-contained examples
of physics at work in the world Many of these real-world “applications” are
also related to the fields of biology and medicine and are labeled BIO.
• Writing that is easy to follow and rigorous The writing is friendly yet
focused; it conveys an exact, careful, straightforward understanding of the
physics, with an emphasis on the connections between concepts.
Instructor Supplements
Note: For convenience, all of the following instructor supplements (except for the
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Trang 25• Choose from a wide range of nationally pre-tested problems that provide accurate estimates of time to complete and difficulty.
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The online exercises are designed to encourage students to confront ceptions, reason qualitatively about physical processes, experiment quantita- tively, and learn to think critically The highly acclaimed ActivPhysics OnLine companion workbooks help students work through complex concepts and under- stand them more clearly More than 420 applets from the ActivPhysics OnLine library are also available on the Instructor Resource DVD for this text.
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ques-Five Easy Lessons: Strategies for Successful Physics Teaching (ISBN
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MasteringPhysics® (www.masteringphysics.com) is a homework, tutorial, and assessment system based on years of research into how students work physics problems and precisely where they need help Studies show that students who use MasteringPhysics significantly increase their scores compared to hand- written homework MasteringPhysics achieves this improvement by providing students with instantaneous feedback specific to their wrong answers, simpler sub-problems upon request when they get stuck, and partial credit for their method(s) This individualized, 24/7 Socratic tutoring is recommended by 9 out
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Pearson eText is available through MasteringPhysics, either automatically
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Trang 26pur-access to the Internet, Pearson eText comprises the full text, including figures
that can be enlarged for better viewing With eText, students are also able to
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Acknowledgments
I want to extend my heartfelt thanks to my colleagues at Carnegie Mellon for
many stimulating discussions about physics pedagogy and for their support and
encouragement during the writing of several successive editions of this book I
am equally indebted to the many generations of Carnegie Mellon students who
have helped me learn what good teaching and good writing are, by showing me
what works and what doesn’t I’m pleased to acknowledge also the contributors
of problems, applications, and other essential elements for this new edition,
including Ken Robinson, Charlie Hibbard, Forrest Newman, Larry Coleman, and
Biman Das Special thanks are due to the Addison-Wesley people, especially
Laura Kenney and Margot Otway, who brought this all together, and to Nancy
Whilton and Kerry Chapman Thanks also to Jared Sterzer at PreMediaGlobal.
Finally, and most importantly, it is always a joy and a privilege to express my
gratitude to my wife Alice and our children Gretchen and Rebecca for their love,
support, and emotional sustenance during the writing of several successive
edi-tions of this book May all men and women be blessed with love such as theirs.
—H.D.Y.
Trang 27Susmita Acharya, Cardinal Stritch University
Hamid Aidinejad, Florida Community College,
Jacksonville
Alice Hawthorne Allen, Virginia Tech
Jim Andrews, Youngstown State University
Charles Bacon, Ferris State University
Jennifer Blue, Miami University
Richard Bone, Florida International University
Phillip Broussard, Covenant College
Young Choi, University of Pittsburgh
Orion Ciftja, Prairie View A&M University
Dennis Collins, Grossmont College
Lloyd Davis, Montreat College
Diana Driscoll, Case Western Reserve University
Laurencin Dunbar, St Louis Community College,
Florissant Valley
Alexander Dzyubenko, California State University,
Bakersfield
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Technology
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Ikka Koskelo, San Francisco State University
Jon Levin, University of Kentucky
David Lind, Florida State University
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Estella Llinas, University of Pittsburgh, Greensburg
Craig Loony, Merrimack College
Rafael Lopez-Mobilia, University of Texas, San Antonio Barbra Maher, Red Rocks Community College
Dan Mazilu, Virginia Tech Randy McKee, Tallahassee Community College Larry McRae, Berry College
William Mendoza, Jacksonville University Anatoli Mirochnitchenko, University of Toledo Charles Myles, Texas Tech University
Austin Napier, Tufts University Erin O’ Connor, Allan Hancock College Christine O’Leary, Wallace State College Jason Overby, College of Charleston James Pazun, Pfeiffer University Unil Perera, Georgia State University David Potter, Austin Community College Michael Pravica, University of Nevada, Las Vegas Sal Rodano, Harford Community College
Rob Salgado, Dillard University Surajit Sen, SUNY Buffalo Bart Sheinberg, Houston Community College Natalia Sidorovskaia, University of Louisiana Chandralekha Singh, University of Pittsburgh Marlina Slamet, Sacred Heart University Daniel Smith, South Carolina State University Gordon Smith, Western Kentucky University Kenneth Smith, Pennsylvania State University Zhiyan Song, Savannah State University Sharon Stephenson, Gettysburg College Chuck Stone, North Carolina A&T State University George Strobel, University of Georgia
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Jaehoon Yu, University of Texas, Arlington Nouredine Zettili, Jacksonville State University Bin Zhang, Arkansas State University
Reviewers and Classroom Testers
Trang 280.1 Exponents 0-1
0.2 Scientific Notation and
Powers of 10 0-30.3 Algebra 0-3
0.4 Direct, Inverse, and Inverse-Square
Relationships 0-60.5 Logarithmic and Exponential
Functions 0-100.6 Areas and Volumes 0-10
0.7 Plane Geometry and
1.3 Standards and Units 3
1.4 Unit Consistency and Conversions 7
1.5 Precision and Significant Figures 9
1.6 Estimates and Orders of Magnitude 11
1.7 Vectors and Vector Addition 12
4.1 Force 994.2 Newton’s First Law 1024.3 Mass and Newton’s Second Law 1044.4 Mass and Weight 109
4.5 Newton’s Third Law 1124.6 Free-Body Diagrams 116
5.1 Equilibrium of a Particle 1285.2 Applications of Newton’s Second Law 1335.3 Contact Forces and Friction 1375.4 Elastic Forces 145
Trang 297
11 12 9
Chapter Work and Energy 188
7.1 An Overview of Energy 188
7.2 Work 192
7.3 Work and Kinetic Energy 196
7.4 Work Done by a Varying Force 200
7.5 Potential Energy 203
7.6 Conservation of Energy 208
7.7 Conservative and Nonconservative
Forces 2127.8 Power 216
Chapter Rotational Motion 267
9.1 Angular Velocity and Angular
Acceleration 2679.2 Rotation with Constant Angular
Acceleration 2709.3 Relationship between Linear and
Angular Quantities 2729.4 Kinetic Energy of Rotation and Moment
of Inertia 2779.5 Rotation about a Moving Axis 281
Chapter Dynamics of Rotational
Motion 29410.1 Torque 29410.2 Torque and Angular Acceleration 29710.3 Work and Power in Rotational Motion 303
10.4 Angular Momentum 30510.5 Conservation of Angular Momentum 30710.6 Equilibrium of a Rigid Body 31110.7 Vector Nature of Angular Quantities 317
Chapter Elasticity and Periodic
Motion 33311.1 Stress, Strain, and Elastic Deformations 33311.2 Periodic Motion 34011.3 Energy in Simple Harmonic Motion 343
11.4 Equations of Simple Harmonic Motion 346
11.5 The Simple Pendulum 35111.6 Damped and Forced Oscillations 354
Chapter Mechanical Waves
and Sound 36512.1 Mechanical Waves 36512.2 Periodic Mechanical Waves 36712.3 Wave Speeds 369
12.4 Mathematical Description
of a Wave 37112.5 Reflections and Superposition 373
Trang 3013
14
15 16
13.3 Archimedes’ Principle: Buoyancy 416
13.4 Surface Tension and Capillarity 419
13.5 Fluid Flow 422
13.6 Bernoulli’s Equation 424
13.7 Applications of Bernoulli’s
Equation 42713.8 Real Fluids: Viscosity
and Turbulence 430
Chapter Temperature and Heat 441
14.1 Temperature and Thermal
Equilibrium 44114.2 Temperature Scales 443
15.3 Kinetic Theory of an Ideal Gas 48615.4 Heat Capacities 492
15.5 The First Law of Thermodynamics 49315.6 Thermodynamic Processes 50115.7 Properties of an Ideal Gas 503
Chapter The Second Law
of Thermodynamics 51616.1 Directions of Thermodynamic Processes 516
16.2 Heat Engines 51816.3 Internal Combustion Engines 52116.4 Refrigerators 523
16.5 The Second Law
of Thermodynamics 52616.6 The Carnot Engine: The Most EfficientHeat Engine 527
16.7 Entropy 53116.8 The Kelvin Temperature Scale 53516.9 Energy Resources: A Case Study
in Thermodynamics 536
Chapter Electric Charge and
Electric Field 54517.1 Electric Charge 54517.2 Conductors and Insulators 54817.3 Conservation and Quantization
of Charge 551
Trang 3117.6 Calculating Electric Fields 560
17.7 Electric Field Lines 563
17.8 Gauss’s Law and Field Calculations 564
18.6 Capacitors in Series and in Parallel 598
18.7 Electric Field Energy 601
19.2 Resistance and Ohm’s Law 620
19.3 Electromotive Force and Circuits 624
19.4 Energy and Power in Electric
Circuits 62919.5 Resistors in Series and in Parallel 632
19.6 Kirchhoff’s Rules 635
19.7 Electrical Measuring Instruments 640
19.8 Resistance-Capacitance Circuits 640
19.9 Physiological Effects of Currents 642
19.10 Power Distribution Systems 643
Chapter Magnetic Field and Magnetic
Forces 65820.1 Magnetism 65820.2 Magnetic Field and Magnetic Force 660
20.3 Motion of Charged Particles in
a Magnetic Field 66720.4 Mass Spectrometers 66920.5 Magnetic Force on a Current-CarryingConductor 670
20.6 Force and Torque on a Current Loop 673
20.7 Magnetic Field of a Long, StraightConductor 677
20.8 Force between Parallel Conductors 67820.9 Current Loops and Solenoids 68020.10 Magnetic Field Calculations 68220.11 Magnetic Materials 685
Chapter Electromagnetic
Induction 69821.1 Induction Experiments 69821.2 Magnetic Flux 700
21.3 Faraday’s Law 70221.4 Lenz’s Law 70621.5 Motional Electromotive Force 70921.6 Eddy Currents 711
21.7 Mutual Inductance 71221.8 Self-Inductance 71421.9 Transformers 71621.10 Magnetic Field Energy 719
21.11 The R–L Circuit 721 21.12 The L–C Circuit 724
Trang 32Chapter Alternating Current 735
22.1 Phasors and Alternating Currents 735
22.2 Resistance and Reactance 738
22.3 The Series R–L–C Circuit 744
22.4 Power in Alternating-Current
Circuits 74822.5 Series Resonance 751
22.6 Parallel Resonance 753
Chapter Electromagnetic Waves 761
23.1 Introduction to Electromagnetic
Waves 76123.2 Speed of an Electromagnetic
Wave 76223.3 The Electromagnetic Spectrum 764
23.4 Sinusoidal Waves 765
23.5 Energy in Electromagnetic Waves 768
23.6 Nature of Light 772
23.7 Reflection and Refraction 774
23.8 Total Internal Reflection 780
23.9 Dispersion 782
23.10 Polarization 783
23.11 Huygen’s Principle 789
23.12 Scattering of Light 791
Chapter Geometric Optics 803
24.1 Reflection at a Plane Surface 803
24.2 Reflection at a Spherical Surface 806
24.3 Graphical Methods for Mirrors 813
24.4 Refraction at a Spherical Surface 815
24.5 Thin Lenses 819
24.6 Graphical Methods for Lenses 825
Chapter Optical Instruments 837
25.1 The Camera 83725.2 The Projector 84025.3 The Eye 84125.4 The Magnifier 84525.5 The Microscope 84725.6 Telescopes 84925.7 Lens Aberrations 852
Chapter Interference and
Diffraction 86226.1 Interference and Coherent Sources 862
26.2 Two-Source Interference of Light 86526.3 Interference in Thin Films 86826.4 Diffraction 873
26.5 Diffraction from a Single Slit 87526.6 Multiple Slits and Diffraction Gratings 879
26.7 X-Ray Diffraction 88226.8 Circular Apertures and Resolving Power 885
26.9 Holography 888
Chapter Relativity 899
27.1 Invariance of Physical Laws 90027.2 Relative Nature of Simultaneity 90327.3 Relativity of Time 905
27.4 Relativity of Length 90927.5 The Lorentz Transformation 91327.6 Relativistic Momentum 91627.7 Relativistic Work and Energy 91927.8 Relativity and Newtonian Mechanics 922
Trang 3328.1 The Photoelectric Effect 933
28.2 Line Spectra and Energy Levels 938
28.3 The Nuclear Atom and
the Bohr Model 94328.4 The Laser 950
28.5 X-Ray Production and Scattering 951
28.6 The Wave Nature of Particles 954
28.7 Wave–Particle Duality 957
28.8 The Electron Microscope 961
Chapter Atoms, Molecules,
and Solids 971
29.1 Electrons in Atoms 971
29.2 Atomic Structure 979
29.3 Diatomic Molecules 98329.4 Structure and Properties of Solids 98729.5 Energy Bands 989
29.6 Semiconductors 99029.7 Semiconductor Devices 99229.8 Superconductivity 995
Chapter Nuclear and High-Energy
Physics 100330.1 Properties of Nuclei 100330.2 Nuclear Stability 100830.3 Radioactivity 101130.4 Radiation and the Life Sciences 101730.5 Nuclear Reactions 1021
30.6 Nuclear Fission 102330.7 Nuclear Fusion 102730.8 Fundamental Particles 102830.9 High-Energy Physics 103030.10 Cosmology 1036
Answers to Odd-Numbered Problems A-8Credits C-1
Index I-1
Trang 34Physics
Trang 36Mathematics Review
0-1
A study of physics at the level of this textbook requires some basic math
skills The relevant math topics are summarized in this chapter We strongly recommend that you review this material, practice end-of- chapter problems, and become comfortable with these as quickly as possible, so that during your physics course, you can focus on the physics concepts
and procedures that are being introduced, without being distracted by unfamiliarity
with the math being used Note that the beauty of physics cannot be enjoyed if you
do not have adequate mastery of basic mathematical skills.
0.1 Exponents
Exponents are used frequently in physics When we write the superscript 4 is
called an exponent and the base number 3 is said to be raised to the fourth
also be raised to a power—for example, There are special names for the
oper-ation when the exponent is 2 or 3 When the exponent is 2, we say that the
quan-tity is squared; thus, means x is squared When the exponent is 3, the quantity
is cubed; hence, means x is cubed.
Note that and the exponent 1 is typically not written Any quantity raised to the zero power is defined to be unity (that is, 1) Negative exponents are
used for reciprocals: An exponent can also be a fraction, as in
The exponent is called a square root, and the exponent is called a cube root.
For example, can also be written as Most calculators have special keys for calculating numbers raised to a power—for example, a key labeled or
The arrangement of seeds in
a sunflower is a classic ple of how natural processes give rise to patterns that can
exam-be expressed by means of fairly simple mathematics.
In this chapter, we will review most of the mathematics you will need for this course.
Trang 37Exponents obey several simple rules, which follow directly from the meaning
of raising a quantity to a power:
1 The product rule:
and
2 The quotient rule:
A special case of this rule is,
3 The first power rule:
4 Other power rules:
21 11
Simplify the expression x and calculate its numerical value when x5 6and y5 3
R E F L E C T Notice that we raised both sides of the equation to the
power As explained in Section 0.3, an operation performed onboth sides of an equation does not affect the equation’s validity
1
Trang 380.2 Scientific Notation and Powers of 10
In physics, we frequently encounter very large and very small numbers, and it is
important to use the proper number of significant figures when expressing a
phys-ical quantity Both these issues are addressed by using scientific notation, in
which a quantity is expressed as a decimal number with one digit to the left of the
decimal point, multiplied by the appropriate power of 10 If the power of 10 is
positive, it is the number of places the decimal point is moved to the right to
power of 10 is negative, it is the number of places the decimal point is moved
to the left to obtain the fully written-out number For example,
In going from 6.56 to 0.00656, the decimal point is moved three places
to the left, so is the correct power of 10 to use when the number is written in
scientific notation Most calculators have keys for expressing a number in either
decimal (floating-point) or scientific notation.
When two numbers written in scientific notation are multiplied (or divided),
multiply (or divide) the decimal parts to get the decimal part of the result, and
multiply (or divide) the powers of 10 to get the power-of-10 portion of the result.
You may have to adjust the location of the decimal point in the answer to express
it in scientific notation For example,
Similarly,
Your calculator can handle these operations for you automatically, but it is
impor-tant for you to develop good “number sense” for scientific notation manipulations.
When adding, subtracting, multiplying, or dividing numbers, keeping the
proper number of significant figures is important See Section 1.5 to review how
to keep the proper number of significant figures in these cases.
0.3 Algebra
Solving Equations
Equations written in terms of symbols that represent quantities are frequently used
in physics An equation consists of an equal sign and quantities to its left and to
its right Every equation tells us that the combination of quantities on the left of
the equals sign has the same value as (that is, equals) the combination on the right
of the equals sign For example, the equation tells us that
that
Often, one of the symbols in an equation is considered to be the unknown,
and we wish to solve for the unknown in terms of the other quantities For
exam-ple, we might wish to solve the equation for the value of x Or we
might wish to solve the equation for the unknown a in terms of x,
t, and Use the following rule to solve an equation:
An equation remains true if any valid operation performed on one side
of the equation is also performed on the other side The operations could be
(a) adding or subtracting a number or symbol, (b) multiplying or dividing by a
number or symbol, or (c) raising each side of the equation to the same power.
Trang 39The Quadratic Formula
Using the methods of the previous subsection, we can easily solve the equation
for x:
The equation is also easily solved by factoring out an x on the
left side of the equation, giving (To factor out a quantity means
to isolate it so that the rest of the expression is either multiplied or divided by that quantity.) The equation is true (that is, the left side equals zero)
if either or These are the two solutions of the equation For
and
nonzero, we cannot use the previous simple methods to solve for x Such an
equation is called a quadratic equation, and its solutions are expressed by the quadratic formula:
Solve the equation 2x21 4 5 22for x.
S O L U T I O N
S E T U P A N D S O LV E First we subtract 4 from both sides This
gives Then we divide both sides by 2 to get
Finally, we raise both sides of the equation to the power
(In other words, we take the square root of both sides of the
equa-tion.) This gives x That is, x 3 or x 3
We can verify our answers by substituting our result back into
the original equation:
so x5 63does satisfy the equation
181 4 5 22,
45 2192 1 4 5
2x21 4 5 2163221
25156!9 5 63
5
12
x25 9
2x25 18
R E F L E C T Notice that a square root always has two possible
val-ues, one positive and one negative For instance,because and 2 2 4 Your calculator willgive you only a positive root; it’s up to you to remember thatthere are actually two Both roots are correct mathematically, but
in a physics problem only one may represent the answer Forinstance, if you can get dressed in minutes, the only physi-cally meaningful root is 2 minutes!
!4
522121
Solve the equation x 5 v0t11 for a.
at2
S O L U T I O N
S E T U P A N D S O LV E We subtract from both sides This gives
Now we multiply both sides by 2 and divide both sides by giving
Trang 40Quadratic formula
For a quadratic equation in the form where a, b, and c are
real numbers and the solutions are given by the quadratic formula:
x 5 2b 6 "b22 4ac
2a
a 2 0,
ax21 bx 1 c 5 0,
Find the values of x that satisfy the equation 2x22 2x 5 24.
so or If x represents a physical quantity that takes
only nonnegative values, then the negative root is physical and is discarded
non-R E F L E C T As we’ve mentioned, when an equation has more than
one mathematical solution or root, it’s up to you to decide whether
one or the other or both represent the true physical answer (If ther solution seems physically plausible, you should review yourwork.)
x5 23
x5 4
Simultaneous Equations
If a problem has two unknowns—for example, x and y—then it takes two
inde-pendent equations in x and y (that is, two equations for x and y, where one
equation is not simply a multiple of the other) to determine their values
uniquely Such equations are called simultaneous equations because you
solve them together A typical procedure is to solve one equation for x in terms
of y and then substitute the result into the second equation to obtain an
equa-tion in which y is the only unknown You then solve this equaequa-tion for y and use
the value of y in either of the original equations in order to solve for x A pair
of equations in which all quantities are symbols can be combined to eliminate
one of the common unknowns In general, to solve for n unknowns, we must
have n independent equations Simultaneous equations can also be solved
graphically by plotting both equations using the same scale on the same graph
paper The solutions are the coordinates of the points of intersection of the
unequal complex numbers and cannot represent physical quantities In such
a case, the quadratic equation has mathematical solutions, but no physical